Most image display devices exhibit some form of color distortions, which depending on the type of display device, could be accompanied by geometric distortions. These distortions are a result of non-ideal geometric behavior and non-ideal color response of the system components. Various causes such as imperfections of the optical components in the system, misalignment of the system components, material manufacturing faults, complicated surfaces in displays, and operational variations in the system can result in distortions. For instance lateral chromatic aberration in an RPTV (Rear Projection TV) or other projection systems is caused by dispersion of light optical lenses in these systems. An optical solution to correct for such a distortion, such as using extra-low dispersion glass, is costly and adds to the complexity of the system.
Visual manifestation of color distortions includes pixel-by-pixel variations, as well as non-uniformity of color, which includes brightness variation across a group of pixels. This causes a signal of fixed chrominance and luminance is seen to vary across the display or differ from its intended perception.
As for geometric distortions, warping algorithms and methods relevant to can be found in the U.S. Pat. Nos. 7,064,770 and 7,126,616, and the United States Patent Application Publication No. 2006/0120620A1, all assigned to Silicon Optix Inc. which are hereby incorporated by reference.
The present invention devises color and geometry distortion correction schemes that apply to a wide variety of displays, are flexible in terms of the types of distortions allowable, and are efficiently executable for real-time image processing.